It allows you to easily access all the partitions inside an image file or inside LVM volume. There's a separate block device for each partition.
You can mount, copy, format, or whatever you need to do and it works just like for "real" partitions. It's important to do this before using the image again for other purposes or starting the guest again!
If you forget to remove the mappings the image might get corrupted when you access the image with other tools or start the guest. Another neat way which works for me, is to simply attach the block device to dom0 as you would to a domU. You should check dmesg and see which device nodes were created for you. Once you are done working with the disk image you can:. Every Xen "file:" backed domU disk uses one loop device in dom0, and if you do "mount -o loop disk.
You can check all the loop devices in use by running "losetup -a". You can also use Xen "phy:" backed LVM volumes instead of disk images. Such an error message may also be indicative of other issues such as the guest crashing and restarting so quickly that xend does not have time to free the older loopback device.
Many people prefer to not install any graphical drivers or X on dom0 for maximum stability. You can still run graphical applications using ssh X11 forwarding. If you're using Windows you can install "xming" and "putty". See this wiki page for a Xen 4. Xen 4. Note that also the dom0 kernel needs to have the blktap2 driver.
Intel e is known to be the best performing emulated NIC. This problem is often related to udev. Do you have udev installed? This error usually has more information in the end revealing the real reason.. Which means exactly what it says.. Run "brctl show" to verify what bridges you have. Create the missing bridge, or edit the VM cfgfile and make it use another correct bridge. So when dealing with these problems always check you have all the required xen backend driver modules loaded in dom0 kernel!
Y interfaces are created by the xen-netback backend driver in dom0 kernel. The frontend driver xen-netfront runs in the kernel of each VM. The same general idea applies to upstream Xen and other distros, but the steps required are probably slightly different. Do you have "xenconsoled" process running in dom0? You should not normally need to specify this option.
PAE is required if you wish to run a bit guest Operating System. In general, you should leave this enabled and allow the guest Operating System to choose whether or not to use PAE. X86 only. This option is enabled by default and usually you should omit it. This option is true for x86 while it's false for ARM by default. True 1 by default. False 0 by default. This option has no effect on a guest with multiple virtual CPUs as they must always include these tables.
This option is enabled by default and you should usually omit it but it may be necessary to disable these firmware tables when using certain older guest Operating Systems. These tables have been superseded by newer constructs within the ACPI tables.
This allows a guest Operating System to map pages in such a way that they cannot be executed which can enhance security. This options requires that PAE also be enabled. This option is enabled by default and you should usually omit it. Alternate-p2m allows a guest to manage multiple p2m guest physical "memory views" as opposed to a single p2m. This option is disabled by default. The mixed mode allows access to the altp2m interface for both in-guest and external tools as well.
Enables limited access to the alternate-p2m capability, ie. Enables or disables HVM guest access to alternate-p2m capability. This option is disabled by default and is available only to HVM domains.
This option is deprecated, use the option "altp2m" instead. Note : While the option "altp2mhvm" is deprecated, legacy applications for x86 systems will continue to work using it. Enable or disables guest access to hardware virtualisation features, e. You may want this option if you want to run another hypervisor including another copy of Xen within a Xen guest or to support a guest Operating System which uses hardware virtualisation extensions e.
Two versions of config syntax are recognized: libxl and xend. Both formats use a common notation for specifying a single feature bit. A few keys take a numerical value, all others take a single character which describes what to do with the feature bit.
Some leaves have subleaves which can be specified as "leaf,subleaf". The bitstring represents all bits in the register, its length must be 32 chars. Each successive character represent a lesser-significant bit. Note: when specifying cpuid for hypervisor leaves 0xxxxx major group only the lowest 8 bits of leaf's 0xxx00 EAX register are processed, the rest are ignored these 8 bits signify maximum number of hypervisor leaves.
Specifies a path to a file that contains extra ACPI firmware tables to pass into a guest. The file can contain several tables in their binary AML form concatenated together. Each table self describes its length so no additional information is needed.
These tables will be added to the ACPI table set in the guest. Note that existing tables cannot be overridden by this feature. The file can contain a set of DMTF predefined structures which will override the internal defaults. Not all predefined structures can be overridden, only the following types: 0, 1, 2, 3, 11, 22, Since SMBIOS structures do not present their overall size, each entry in the file must be preceded by a 32b integer indicating the size of the following structure.
The VM generation ID is a bit random number that a guest may use to determine if the guest has been restored from an earlier snapshot or cloned.
Specifying this option as a number is deprecated. Specifies that periodic Virtual Platform Timers should be aligned to reduce guest interrupts. Enabling this option can reduce power consumption, especially when a guest uses a high timer interrupt frequency HZ values. The default is true 1. Delay for missed ticks. Do not advance a vCPU's time beyond the correct delivery time for interrupts that have been missed due to preemption. No delay for missed ticks. As above, missed interrupts are delivered, but guest time always tracks wallclock i.
No missed interrupts are held pending. Instead, to ensure ticks are delivered at some non-zero rate, if we detect missed ticks then the internal tick alarm is not disabled if the vCPU is preempted during the next tick period.
One missed tick pending. Missed interrupts are collapsed together and delivered as one 'late tick'. Guest time always tracks wallclock i. The following options allow Paravirtualised features such as devices to be exposed to the guest Operating System in an HVM guest.
Utilising these features requires specific guest support but when available they will result in improved performance. Enable or disable the Xen platform PCI device. The presence of this virtual device enables a guest Operating System subject to the availability of suitable drivers to make use of paravirtualisation features such as disk and network devices etc.
Enabling these drivers improves performance and is strongly recommended when available. The following groups of enlightenments may be specified:. These enlightenments can improve performance of Windows Vista and Windows Server onwards and setting this option for such guests is strongly recommended.
This group is also a pre-requisite for all others. If it is disabled then it is an error to attempt to enable any other group. These enlightenments can improve performance of Windows 7 and Windows Server R2 onwards. This enlightenment can improve performance of Windows 8 and Windows Server onwards. This enlightenment can improve performance of Windows 7 and Windows Server R2 onwards. This set incorporates use of hypercalls for remote TLB flushing. This enlightenment may improve performance of Windows guests running on hosts with higher levels of physical CPU contention.
This enlightenment may improve performance of guests that make use of per-vCPU event channel upcall vectors. Note that this enlightenment will have no effect if the guest is using APICv posted interrupts. This group incorporates the crash control MSRs. These enlightenments allow Windows to write crash information such that it can be logged by Xen. This set incorporates use of a hypercall for interprocessor interrupts.
This enlightenment may improve performance of Windows guests with multiple virtual CPUs. This set enables new hypercall variants taking a variably-sized sparse Virtual Processor Set as an argument, rather than a simple bit mask. This group when set indicates to a guest that the hypervisor does not explicitly have any limits on the number of Virtual processors a guest is allowed to bring up. It is strongly recommended to keep this enabled for guests with more than 64 vCPUs.
This set enables dynamic changes to Virtual processor states in Windows guests effectively allowing vCPU hotplug. Groups can be disabled by prefixing the name with '! So, for example, to enable all groups except freq , specify:. For details of the enlightenments see the latest version of Microsoft's Hypervisor Top-Level Functional Specification. The enlightenments should be harmless for other versions of Windows although they will not give any benefit and the majority of other non-Windows OSes.
However it is known that they are incompatible with some other Operating Systems and in some circumstance can prevent Xen's own paravirtualisation interfaces for HVM guests from being used. The viridian option can be specified as a boolean. A value of true 1 is equivalent to the list [ "defaults" ], and a value of false 0 is equivalent to an empty list. The following options control the features of the emulated graphics device. Sets the amount of RAM which the emulated video card will contain, which in turn limits the resolutions and bit depths which will be available.
When using the qemu-xen-traditional device-model, the default as well as minimum amount of video RAM for stdvga is 8 MB, which is sufficient for e. For the upstream qemu-xen device-model, the default and minimum is 16 MB. For the upstream qemu-xen device-model, the default and minimum is 8 MB.
If videoram is set less than MB, an error will be triggered. If your guest supports VBE 2. Windows XP onwards then you should enable this. Selects the emulated video card. Options are: none , stdvga , cirrus and qxl. The default is cirrus. Then go through the initial format, copy, and so on. When the first phase of Windows Setup completes and the VM turns off, change the config file to read:. If you need to change the HAL later on—for example, if you decide to move from a uniprocessor to a multiprocessor configuration—we recommend reinstalling Windows.
Just create a machine from the virt-manager GUI, select Fully Virtualized rather than Paravirtualized in the appropriate dialog, and indicate the location of Windows install media either an ISO file or physical. Put your definition for the first hard drive in the appropriate place, of course. Mouse tracking, for example, can be kind of iffy out of the box.
One useful trick when working with the VNC framebuffer under Windows is to specify a tablet as the pointing device, rather than a mouse.
This improves the mouse tracking by using absolute positioning. One last minor annoyance: Sometimes the VNC mouse and keyboard interface just stops working or else the display stops updating. These have the advantage of allowing the virtual machine to handle its own graphics tasks rather than involving an emulator in dom0.
RDP is also a higher-level, more efficient protocol than VNC, analogous to X in its handling of widgets and graphics primitives. We recommend using it if possible. On other platforms, the open source rdesktop client allows you to access Windows machines from Unix-like operating systems including Mac OS X.
Simply run the following:. Now you have Windows running. This would be a good time to make a backup of your clean Windows install so that you can conveniently reimage it when something goes wrong. We would not presume to instruct you in this regard. Thus, it would be a good idea to decide on a hardware configuration ahead of time and keep it constant to avoid the computer demanding reactivation. Neither of these modes supports any sort of acceleration. If you see this, congratulations!
Using Linux Tools. System Builds. BSD Networking. Build NFS Server. Build Storage Backend. Setting up CARP. Setting up HAST. Installing on older computers. Installing on USB Thumbdrive. Using PF for Firewall. LetsEncrypt - recovering from bad install. Using certbot. Debian Upgrade Problems. Devuan APT. Devuan Recipes. Serial Port Console under Devuan Linux.
Unix Virtualization. KVM on personal workstation. KVM on server with libvirt. KVM Quick Reference. Linux Virtual Machine Managers. Dynamically Mount Xen Block Devices. Gracefully Shut down non-standard virtuals.
Xen DOM0. Xen Networking. Tricks and Techniques.
0コメント